In the art, DE 10 2007 003 956 A1 discloses a speed control of an engine and a hydrostatic transmission, whereas a vehicle drive speed request is set by an accelerator pedal and an inching percent, i.e., the maximum vehicle speed is reduced, as the fully pressed pedal produces vehicle speed below the maximum speed. There is a fixed and parametrized relation from vehicle speed request to both the engine rpm and hydrostatic transmission gear ratio.
In addition, EP 2 949 533 A1 teaches the control of an engine depending on the predicted operation of a vehicle in order to reduce fuel consumption.
There is, however, a need for a control of a drive assembly of a vehicle, which provides for fuel efficiency, but also keeps the engine powerful and running at a requested speed in spite of the load generated by a hydrostatic transmission propelling the vehicle.